Association of osteopontin and shrunken pore syndrome with hospitalization for renal failure in acute heart failure patients

Abstract Background Shrunken pore syndrome (SPS) emerges as a distinctive manifestation of glomerular filtration dysfunction mainly manifested by the impairment of moderate-sized molecular filtration, distinguished by a variance in renal filtration between cystatin C and creatinine. SPS exhibits correlations with adverse prognosis of various cardiovascular diseases. A decline in renal function correlates with a poor prognosis among individuals with heart failure (HF). Osteopontin (OPN), a protein involved to bone mineralization, has been linked to deteriorating renal function and heightened risk for adverse outcomes in patients with chronic kidney disease. Purpose To explore if OPN and SPS are associated with hospitalization for renal failure in patients with acute HF. Methods Cystatin C and creatinine were analyzed in 395 hospitalized HF patients, of which 324 also had osteopontin (OPN) analyzed using a proximity extension assay. SPS was calculated using the CKD-EPI Equations for Glomerular Filtration Rate and defined as a cystatin C-based estimated glomerular filtration rate (eGFR) <60% of the creatinine based eGFR. Hospitalization for renal failure was extracted from regional registries using ICD10 codes N17-N19. Logistic and Cox regression models were deployed to explore a) OPN’s association with SPS; b) OPN’s association with hospitalization for renal failure; and c) SPS’s association with hospitalization for renal failure, adjusting for age, sex, systolic blood pressure and use of renin-angiotensin-aldosterone system (RAAS) inhibitors. Results The study population had a mean age of 74.8 (±12.0) years, 32.4% were women and 104 (26.5%) patients presented with SPS (Table 1). During the median follow-up period of 71 (interquartile range 56-88) months, 35 (8.9%) patients were hospitalized for renal failure. OPN was associated with the prevalence of SPS (OR 1.66; 95%CI 1.08-2.27; p=0.002), as well as with higher risk of hospitalization due to renal failure (HR 2.71; 95%CI 1.61-4.56; p<0.001). Further, also prevalent SPS was associated with higher risk of hospitalization due to renal failure (HR 2.44; 95%CI 1.14-5.24; p=0.022). Conclusions Here, we demonstrate that higher OPN levels are associated with a higher prevalence of SPS and an elevated risk of hospitalization due to renal failure among patients with HF. Additionally, the presence of SPS was associated with a higher risk of renal failure-related hospitalizations. These findings highlight the potential utility of OPN and SPS as biomarkers for identifying heart failure patients at risk of renal function decline, underscoring the importance of early risk stratification and targeted interventions in this population.